Stove-door knob



(No Model.)

- W. J. IRWIN.

STOYE 1190B KNOB. 7

No. 311,762. Patented Feb. 3,1885

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WVILLIAM JAMES IRYVIN, OF READING, PENNSYLVANIA.

STOVE-DOOR KNOB.

SPECIFICATION forming part of Letters Patent No. 311,762, dated February 3, 1885.

Application filed March 20, 1884.

To all whom it may concern.-

Be it known that I, WILLIAM J. IRWIN, a citizen of the United States, residing at the city of Reading, county of Berks, State of Pennsylvania, have invented a new and useful Improvement in Stove Door Knobs, of which the following is a specification.

My invention relates to improvements in the construction of knobs intended to be ap plied to heated surfaces; and the object of the improvement is to retain said knobs, although attached to heated surfaces, in a cool condition, so that they can be handled.

It is my desire also to furnish the stove trade with an ornamental ventilated knob adapted to all the requirements of stovemanufacturers, that will Withstand the rough handling of shippers and users without disfigurenient.

The above objects are attained in the use of the improvement shown in the drawings herewith, forming part of this specification, and in which similar letters indicate similar parts throughout.

Figure 1 represents the knob complete, ready for attachment; Fig. 2, a plan view of the top of the cap, and a section of the same; Fig. 3, an elevation of the body-piece detached from the cap, and a plan of the same. Fig. 4 represents two views showing two different methods of attachment for the knob. Fig. 5

is a vertical section of Fig. 1, through the body of the shell A on one side, and through an opening, A on the opposite side.

Numerous attempts have been made to secure a non-conducting doorknob for attachment to heated surfaces by perforating the shell and by filling the same with a non-conducting substance, but all have failed commercially, owing to the expense attendant upon-their construction.

The body-section of the knob is a hollow shell of any suitable shape, preferably in the form of the frustum of a cone, and having the smaller end or point of attachment perforated at A for the passage of the shank of the screw, as shown in Fig. 5. This perforation may be threaded,as shown on the left in Fig. 4:. Then the perforation is not threaded, the separable (No model.)

parts are loose until locked by the turning of the threaded end of the screw D into the tapped hole of the piece to which it is to be secured. hen the perforation is threaded, the screw 0 is threaded far enough up to engage therewith, whereby the screw 0 can be screwed into the threaded base of the bodypiece A, to hold the separable parts together, prior to its attachment to the door E or other article. To this mode I give the preference, the closure of the cap B upon the body-piece being more positive.

To secure ventilation, and consequent coolness of the knob, I cut the shell of the bodypiece at three or more points, as I may think desirable, to form spaces A, which extend to the upper edge thereof, and are configured withreference to the easy molding of the bodypiece. The top edge or rim, A, of the bodypiece is serrated to reduce the radiating-surface in contact with the cap B, and is tapered off on the outside edge to fit the recess B in the cap, which is of a corresponding form. The pieces are so proportioned that on assembling them the cap B shall rest on the shell A and the serrated rim shall not touch the bottom of the recess 13". The cap is drawn down upon the body-piece A by the bolt 0, passing through the perforation A in the cap. The separable parts A B may both be cast of iron or brass, or the body of one metal and the cap of another, as may be thought preferable. In either case a knob of considerable lightness and strength is secured, and one ordinarily cool to the touch.

I am aware that I am not the first to produce a stovedoor knob arranged as a nonheat-conducting knob, or in separable parts. See patent to Miles W. Gardner, No. 168,734, October 11, 1875. This knob is a hollow cast base-piece with air-notches in the rim of the same, and provided with a cast or spun cap, the two portions being separated by a wooden disk, which is relied upon as the non-conductor and furnishes the grasping portion of the knob. In my knob the air circulating freely within the shell and around the screw 0 keeps the same in a comparatively cool condition, and

the knob body and cap being cast have all the strength requisite to prevent crushing in securing the same upon the doors or other articles to which they may be attached.

Having shown the construction, use, and 5 advantages of my improvements, I desire to secure by Letters Patent the following claim thereon:

A ventilated metallic knob for stove-doors or for heated plates, made in separable parts, IO as described, the base'piece A being provided with a conical serrated rim, A and the cap B, having an overlapping reversely-coned recess, 13 adapted to fit over the basepiece, whereby the cap is made self-centering, substantially as and for the purpose set forth.

VILLIAM JAMES IIflVIN.

Witnesses:

THOMAS P. KINSEY, JOHN B. GRISSINGER. 

